Pick an empty User Defined Digit Map slot:
Block list, Black list, Circle of Distrust, or Circle of Annoyance:
User Settings -> User Defined Digit Maps -> User Defined Digit MapX -> Label : blk
User Settings -> User Defined Digit Maps -> User Defined Digit MapX -> DigitMap :
(1999|0000000999|11999|10999|110000000999)
Voice Services -> SP1 Service -> X_InboundCallRoute : {(Mblk):spX(2674365139)},{ph}
Voice Services -> SP2 Service -> X_InboundCallRoute : {(Mblk):spX(2674365139)},{ph}
(Obi110) Physical Interfaces -> LINE Port -> InboundCallRoute : {(Mblk):spX(2674365139)},{ph}
change spX (3 places) to wherever you have google voice installed (sp1 or sp2).
Routing the call to :spX(2674365139) rather than nowhere (nothing after the ":") prevents the caller from ending up in your google voice mailbox when the inbound call is not answered.